So Much "Harshness"

In perusing the various boards, both here and elsewhere ("we toured the world and elsewhere")one theme that seems to be prevalent is "my system sounds harsh" or "this cd player seems harsh", etc.

Why are complaints of "harshness" so common? Are people selecting the wrong components based on dealer demos where the "brighter" components sound better due to additional detail? Is it caused by a taste for music which is intentionally mixed bright to be heard better on transistor radios? (The radios are gone, but the mixing tradition lives on, doesn't it?) Are they simply listening louder than their systems will tolerate without deteriorating? I think this is pretty common. It costs a lot of money for a system that will deliver audiophile sound at high volume.

What do you think?